Phase change memory devices with contact surface area to a phase changeable material defined by a sidewall of an electrode hole and methods of forming the same

Abstract

Phase change memory devices and methods of making phase changeable memory devices including a heating electrode disposed on a substrate are provided. The heating electrode includes an electrode hole in the heating electrode. A phase change material pattern is provided in the electrode hole and contacts a sidewall of the electrode hole. In some embodiments, the electrode hole extends through the heating electrode. In some embodiments, the phase changeable material pattern only contacts the electrode at a sidewall of the electrode hole.

1. A phase change memory device, comprising:
 a heating electrode disposed on a substrate, the heating electrode including an electrode hole extending through the heating electrode; and 
 a phase change material pattern in the electrode hole and contacting a sidewall of the electrode hole. 
 
   
   
     2. The device of  claim 1 , further comprising an insulation layer on the heating electrode and including a guide hole extending through the insulation layer,
 wherein the phase change material pattern is disposed on the insulation layer and in the guide hole, and 
 wherein a portion of the phase change material pattern extends through the guide hole to the electrode hole and contacts the sidewall of the electrode hole. 
 
   
   
     3. The device of  claim 2 , wherein the sidewall of the electrode hole and the sidewall of the guide hole are arranged in a straight line. 
   
   
     4. The device of  claim 2 , wherein the sidewall of the guide hole is inclined, and a bottom end width of the guide hole is smaller than a top end width the guide hole. 
   
   
     5. The device of  claim 2 , further comprising a spacer on the sidewall of the guide hole and on the heating electrode and wherein a width of the electrode hole is smaller than a width of the guide hole. 
   
   
     6. The device of  claim 1 , further comprising a conductive capping pattern disposed on a top surface of the phase change material pattern, wherein the conductive capping pattern has a sidewall aligned to a sidewall of the phase material pattern. 
   
   
     7. The device of  claim 1 , further comprising:
 a lower dielectric layer interposed between the heating electrode and the substrate; and 
 a lower plug extending through the lower dielectric layer to contact a predetermined region of the substrate, a top surface of the lower plug being electrically connected to the heating electrode. 
 
   
   
     8. The device of  claim 7 , further comprising:
 an upper dielectric layer covering the phase change material pattern; and 
 an upper plug extending through the upper dielectric layer to electrically connect to the phase change material pattern. 
 
   
   
     9. The device of  claim 8 , wherein the lower plug and the upper plug are aligned to a virtual line perpendicular to a top surface of the substrate. 
   
   
     10. The device of  claim 8 , wherein the guide hole and the electrode hole are offset from the lower plug and/or the upper plug. 
   
   
     11. The device of  claim 1 , wherein the phase change material pattern only contacts the heating electrode through a sidewall of the electrode hole.